Detection of human respiration using square-wave modulated electromagnetic impulses

A technique for monitoring human respiration utilizing square-wave modulated electromagnetic impulses is presented. Lung volume changes associated with human respiration alter the time-amplitude spectrum of a reflected electromagnetic impulse, while the Brillouin-precursor associated with impulse propagation through dispersive media enables detection through otherwise opaque barriers. Results of numerical simulations and experiments are presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 339–343, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10759